title: Biodegradation of resin composites and adhesives by oral bacteria and saliva: a rationale for new material designs that consider the clinical environment and treatment challenges.
abstract: OBJECTIVE
  To survey the recent literature from the late 1980s to recent years in order to assess the relationship between resin degradation, catalyzed by biological factors, and clinical failure outcomes such as marginal breakdown.
  
  
  METHODS
  The literature shows that degradation occurs in many manufacturers' products despite varied vinyl acrylate compositions. The authors examine salivary enzyme activity and their ability to degrade the polymeric matrix of resin composites and adhesives, as well as oral microorganisms that can promote demineralization of the tooth surface at the marginal interface. A survey of recent research relating matrix metalloproteinase (MMPs) to the degradation of the exposed collagen at the dentin adhesive interface is also discussed in the context of marginal breakdown.
  
  
  RESULTS
  The literature provides strong support that together, the above factors can breakdown the marginal interface and limit the longevity of resin composite restorations. The authors have found that the field's current understanding of resin biodegradation in the oral cavity is just beginning to grasp the role of bacteria and enzymes in the failure of resin-based restorations.
  
  
  CONCLUSIONS
  Knowledge of these biodegradation processes is pertinent to areas where innovative strategies in the chemistry of restorative materials are anticipated to enhance the longevity of resin composites.
authors.affiliation: Institute of Biomaterials and Biomedical Engineering, University of Toronto, Ontario, Canada.
authors.forename: Yasaman
authors.initials: Y
authors.lastname: Delaviz
authors.affiliation: Institute of Biomaterials and Biomedical Engineering, University of Toronto, Ontario, Canada; Faculty of Dentistry, University of Toronto, Ontario, Canada.
authors.forename: Yoav
authors.initials: Y
authors.lastname: Finer
authors.affiliation: Institute of Biomaterials and Biomedical Engineering, University of Toronto, Ontario, Canada; Faculty of Dentistry, University of Toronto, Ontario, Canada. Electronic address: paul.santerre@dentistry.utoronto.ca.
authors.forename: J Paul
authors.initials: JP
authors.lastname: Santerre
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D003188:Composite Resins / Q000378:metabolism*; D006801:Humans; D009055:Mouth / Q000382:microbiology*; D012463:Saliva / Q000378:metabolism*
chemical_list: D003188:Composite Resins
keywords: Bacteria; Biodegradation; Dental restorative materials; Esterases; Hydrolysis; Matrix metalloproteinase (MMPs); Resin adhesives; Resin composites; Streptococcus mutans; Toxicity